3 Main Types of Asphalt Shingles 101
So you had your eye on a new Pavatti… If you don’t know what a Pavatti is, stop reading and go get your eyes on one, mainly so that you can distract yourself from that growing yellow stain on your ceiling. It can’t be from the roof right? Maybe it’s just attic rain? You know, frozen water droplets or frost in your attic caused by poor ventilation and the accumulation of moisture in the attic, which then freezes during cold temperatures. Just in time for a warm spring thaw where the ice droplets rain down on you from the roof above. So you call your Edmonton roofing company, or maybe try out a new one you’ve seen around. Yet they tell you to turn down your humidifier and schedule your roof inspection to ensure proper ventilation. And then run your bathroom fan 30 minutes before and after your showers and baths. Make sure you use your kitchen exhaust fan while cooking. Handled, you've got this.
So after a few years, you finally got enough money for that new tiffany blue Pavatti. And a freak winter windstorm comes through and congratulations you already got money for the new roof that you d
idn’t know you needed. Love that for you. So what type of roof do you consider? You've already ruled out rubber, metal, clay, cedar and solar tiles. Assuming you don’t reside in an architecturally controlled neighborhood where your choice is made for you by the governing body. So you landed on the cult classic asphalt shingles, they are by far the most popular, versatile, simple to install and cost-effective choice. And the majority of shingle manufacturers provide a 30, 40, and higher costing 50 year warranty. Hold on there though, there are two types, organic and fiberglass. And before you rule out Organic
Types of asphalt shingles
Organic shingles have been around the longest, they consist of a mat made of recycled paper, or some other product made of wood component, impregnated with asphalt and compressed under high pressure. They are more flexible than their Fiberglass counterparts, making them easier to install in cold weather and tear resistant. Organic shingles are heavier and therefore more resistant to strong winds, they also withstand changes in temperature. Because of the flexibility organic shingles are more forgiving on older roofs, able to hide imperfections. Which because of the soaring cost of lumber and sheathing. This is definitely a win for the homeowner’s.
Fiberglass asphalt shingles have a layer of glass fibres instead of paper. They are referred to as composition shingles.They are lighter, because less asphalt is used during manufacturing. less expensive, more heat-resistant and the ''feet'', or notched ends, are less likely to lift, a problem often encountered on older roofs. Fiberglass apply less strain on your roofing system, and because the shingles have less asphalt, they are more environment-friendly! They also boast a higher fire rating. Go figure organic shingles are actually worse for the ozone and the environment.
Asphalt shingle components
Both types are composed of several layers.
- Granular Surface Layer - Granules are those little colored specks that after the storm, or rain are the specks in your gutters, eaves lawn and driveway. They constitute the superficial layer of asphalt shingles, providing colour and UV protection. This granite-like coating comes from basaltic deposits, including basalt and rhyolite, which are not only hard and durable but opaque to keep UV rays from deteriorating the asphalt. Certain granules are engineered to reflect heat and keep roof temperatures cool. They may also contain additives to prevent mould
Asphalt Coating - Asphalt is the waterproofing agent applied during manufacturing which ensures protection. The thickness of the asphalt layer determines the weight of the shingle. Architectural shingles have two layers of asphalt, with a fibreglass mat in the centre
- Mat or Base Layer - The material used for the mat/base differentiates the type of shingle. For organic shingles it is made of organic paper/wood variant saturated with asphalt, whereas the fibreglass shingles are reinforced with a fibreglass mat. This membrane acts as a frame, holding the other layers together. It is integral that it’s integrity does not waver or fault in different weather, it must be resistant and weather stable
- Adhesive Tabs - Shingles come with heat-activated adhesive tabs. Never drive a nail through these adhesive tabs, which could prevent shingles from fusing or locking to the roof deck. It is also vital that the adhesive tabs seal in a timely manner to manufacturer’s specifications so that debris does not build up and cause the adhesive tabs to degrade and inability to efficiently seal one shingle to the next.
- Nailing Strip - Varies by shingle manufacturer, giving some an advantage over others in cooler, cold, warmer and hot environments. Shingles must be nailed using an approved nail and not stapled, which makes them more vulnerable to cracks. Nail heads should be visible on the surface without being driven too deep.
Shingles are designed to work with other roofing components to create a complete weather proof system, which is why you want to choose a certified roofing company who has an up to date certification in good standing. This does not guarantee proper roofing practices but it helps to lower the chance that you will get an unwelcome surprise. Homeowners find out 5-10 years into their 40 years shingle life, that they received a lower grade roofing experience than initially agreed upon. Whether they found someone cheaper, they hired a family member or friend, or they didn’t properly vet the roofing company. Nobody wants to find out a quarter way into an agreement that they are not covered.
You probably wouldn’t let your father in law perform maintenance on your boat on the ground without adequate certification so why is he up on your roof? Insurance companies can dishonor coverage of your roof if damage or installation is proved to be as a result of negligence or insufficient experience.
Additional Properties
- Wind-Resistant - The combination of adhesive and nails provide shingles with wind-resistance. The majority of shingles can resist winds more than 100 km/h with regular installation, however certain types of shingles with high-wind installation provide protection and resistance to winds up to 220 km/h. Which is definitely beneficial when you have a new roof and you learn a new name for a winter storm, and less than two months later another winter storm comes through.
- Solar Reflectance Index (SRI) -Shingle manufacturers have been busy developing a more solar-reflective, and ensuring cooler attic spaces. The granular layer reflects the sun's rays without affecting roof-colour.
Where do we wind up? Well we still have to take into consideration a few of unique variables.
Roof slope
For an walk-able slope roofs over (more than 6/12 and 7/12) or high-slope roof (8/12 to 12/12), architectural shingles are recommended. because of the higher quality, wind resistance, and lack of snow, ice and water unable to sit as long. Architectural asphalt shingles are typically a higher quality, ranging from mid grade to high grade. They have more of a visual appeal due to their make up and texture.
Asphalt shingles should never be installed on roofs with a slope less than 2:12 (8.5°).
Exposure
